1603 Submissions

Authors:Raji HeyrovskaComments: Pages. In Eqs. 3 and 4a, the last terms should read 1-R(+) and -52.01 resply.

It has been known for over a century that the interfacial tension of mercury dipping in electrolyte solutions changes with applied potential following a near parabolic course called the electrocapillary curve. Solution components adsorbable on mercury produce asymmetric curves with respect to the potential at the electrocapillary maximum. A simple mathematical description of this asymmetry has so far exercised and eluded many scientists. Here, the author shows a simple linear relation which describes the electrocapillary curves, using the existing data.
Category:Chemistry

The Haber-Bosch process is the main industrial method for producing ammonia from diatomic nitrogen and hydrogen. Very demanding energetically, it uses an iron catalyst, and requires high temperature and pressure. Any improvement of the Haber process will have an extreme scientific and economic impact. We report a significant increase of ammonia production using hydroxylated graphene. Exploiting the polarity difference between N2/H2 and NH3, as well as the universal proton acceptor behavior of NH3, we demonstrate a strong shift of the equilibrium of the Haber-Bosch process towards ammonia. Hydroxylated graphene provides the polar environment favoring the forward reaction, and remain stable under the investigated thermodynamic conditions. Ca. 50 kJ mol-1 enthalpy gain and ca. 60-70 kJ mol-1 free energy gain are achieved at 298 1300 K and 1 1000 bar, strongly shifting the reaction equilibrium towards the product. A clear microscopic interpretation of the observed phenomenon is given using electronic structure calculations and real-time reactive simulations. The demonstrated principle can be applied with many polar groups functionalizing a substrate with a high surface area, provided that the system is chemically inert to H2, N2 and NH3. The modified Haber-Bosch process is of significant importance to the chemical industry, since it provides a substantial increase of the reaction yield while decreasing the temperature and pressure, thereby, reducing the cost.
Category:Chemistry

The nature of the chemical bond has intrigued many a mind. Bohr’s theory of the hydrogen atom, which celebrated its centennial recently, gave the correct value but a negative sign for the energy. As this would imply that the energy of the Universe, which consists of 70% hydrogen, is negative, the author was dissatisfied with it. So she proposed a modified approach to the problem, which showed that the energy is positive. Moreover, she found that the Bohr radius is divided into two Golden sections pertaining to the electron and proton. This idea cascaded into the finding that all bond lengths in small as well as large molecules are simply exact sums of the appropriate atomic and or Golden ratio based ionic radii of adjacent atoms or ions. Over the years, this has proved to be correct for various types of bonds, including hydrogen bonds, bonds in graphite and in benzene dimers.
Category:Chemistry

Solution Chemistry Simplified Based on Arrhenius' Theory of Electrolytic Dissociation and Hydration for All Concentrations Collected Research Work, Dedicated to Svante August Arrhenius (1859 – 1927).

Arrhenius theory of partial dissociation of electrolytes rose to its heights and fame when he was awarded the Nobel Prize (1903). While the theory was still being developed to account for the non-ideal properties of electrolytes at higher concentrations, it was unfortunately replaced by Lewis’ empirical concepts of activity and activity coefficients. With the near success of the Debye-Huckel theory of inter-ionic interactions for very dilutions, the latter was erroneously extended over the next few decades by extended parametrical equations to higher concentrations assuming complete dissociation at all concentrations. This eventually turned solution theory into a mere catalogue of parameters. Therefore, the present author abandoned it all and started systematically analyzing the available experimental data as such. She found that with the degrees of dissociation and ‘surface’ and ‘bulk’ hydration numbers obtained from vapor pressure data, properties of electrolytes could be explained quantitatively over the whole concentration range, using simple mathematical equations.
Category:Chemistry

Study on Properties Analysis of Knitwear After Acid Wash

This article deals with the investigation on the effect of the acid washing (with thermocol balls and potassium permanganate) on different properties of three knitted garments (Single Jersey 100% Cotton T-shirt, Single Jersey 95% Cotton 5% Spandex T-Shirt and 1×1 Rib100% Cotton T- Shirt). Typical washing procedures and techniques were followed and then physical properties were analyzed under standard condition. It is observed that fabric weight, CPI, WPI, spirality and shrinkage increase while bursting strength, stitch length absorbency decrease after washing treatment. PH of all the samples is under controlled and lies between 7 – 8. There is no change in pilling, colorfastness to wash, water and dry rubbing while a little bit decrease in wet rubbing.
Category:Chemistry